Patients have the right to expect the radiation to be used in a safe and effective manner. It must be emphasized that there are no prescribed limits on radiation doses to patients. This means that no amount of radiation is considered too much for a patient when the procedure is justified by the doctor. The doctor will consider the benefits versus the risk.

In medical applications, radiation doses must be sufficient for obtaining adequate diagnostic information and for effective treatment. On the other hand, an examination that does not help medical management is inappropriate, no matter how small the dose is. The very low radiation doses that are received during imaging procedures generally produce no adverse effects. However, it is appropriate to reduce the dose to the lowest amount that is necessary to produce the image quality that is required for a diagnosis.

Advances in medical imaging techniques are allowing doctors to detect more diseases and make ever more accurate diagnoses. But special attention should be paid to the use of high-tech scanning procedures, which overuse may unnecessarily expose patients to increased radiation levels.

There are well established guidelines and recommendations from a number of international organizations on justification and optimization of medical radiation doses:

• World Health Organization. Medical imaging specialists call for global referral guidelines.
• IAEA - Radiation Protection of patients (RPOP).

• Radiological Protection for Medical Exposure to Ionizing Radiation Safety Guide 

• Applying Radiation Safety Standards in Diagnostic Radiology and Interventional Procedures using X Rays.

• Applying Radiation Safety Standards in Nuclear Medicine. 

• International Basic Safety Standards for Protection against Ionizing Radiation and for the Safety of  Radiation Sources.

• ICRP 84 — Pregnancy and medical radiation.

• ICRP 87 - Managing Patient Dose in Computed Tomography (CT).

• Whole-body computerized tomography screening should not be performed. Position statement of the Health Physics Society.